GEOLOGICAL RErOET. 267 



growth of various grasses, among which the short but highly nutritious buffalo-grass, 

 Ihichloc, ihutyloides, and a similar one, Boutdona oligostachia, are particularly worth 

 mentioning. During the summer months they would afford fine grazing to innumer- 

 able herds, especially of sheep. Such is the case in many parts of the district, wher- 

 ever the soil has a slight admixture of clay; but many hundreds of square miles are 

 too sandy or gravelly to produce much of these nutritious grasses, and must be con- 

 sidered as utterly worthless. The country between Ash Hollow and Scott's Bluffs is 

 of this nature, as are also large areas on the uplands at a distance from the river, along 

 Pole Creek, &c. 



The flat river-bottoms in the neighborhood of Fort Kearney are prevailingly sandy. 

 Near the river the upper soil was found only 6 inches deep, light arenaceous and mixed 

 with humus, and of fair quality; the next 4 inches consisted of such soil mixed with 

 much sand, and the subsoil, from a depth of 10 inches down, was composed of nearly 

 pure river-sand, with only little clay. Everywhere about there water can be struck 

 at a depth of a few feet, and therefore the soil is kept moist, and coarse swamp grasses 

 grow abundantly. Tillage will succeed there to some extent, and will be made to pay 

 on account of the lively local demand of the passing traffic. 



The most promising point for agriculture on that line is a limited space near the 

 forks of Platte River, at Cottonwood Spring. At Fort Laramie the soil is dry, sandy, 

 and poor, and but little can be grown, the more so because the season is very short, 

 with late frosts and early snows. Small grain could probably be raised at various 

 points in that neighborhood with the aid of irrigation. The same will apply to some 

 valleys at the immediate foot of the mountains, off the main road. 



The scarcity, and over-long stretches, utter absence of timber or fuel of any kind, 

 except the dung of animals, have frequently been noticed. Lignite has been found 

 in various localities south of the road, along the foot of the Rocky Mountains, but not 

 near the road, and I have not had an opportunity to examine it; it is probably similar 

 to that of the next section. 



Building-material is very scarce in the eastern part of this district, but in the 

 western part, at numerous points, rocks can be quarried, some of which will bear any 

 weight, while others are fit only for light masonry. Part of the houses at Fort Lara- 

 mie have been built of adobes, and such can be made wherever the strata are slightly 

 argillaceous. 



